Re: [PATCH v2 0/3] powerpc/crash: protect kdump from active watchdogs

[Ritesh Harjani (IBM) <ritesh.list@gmail.com>]

Sourabh Jain <sourabhjain@linux.ibm.com> writes:

> On 13/07/26 10:51, Ritesh Harjani (IBM) wrote:
>> Sourabh Jain <sourabhjain@linux.ibm.com> writes:
>>
>>> Changelog:
>>> ==========
>>>
>>> v2:
>>>   - Move H_WATCHDOG definitions to a common header for shared use
>>>     across pseries code. 1/3
>>>   - Added a new patch to handle pseries watchdog device registration
>>>     failure. 2/3
>>>   - Stop active watchdogs in crash hanlder. 3/3 Ritesh
>>>   - Add suggested-by tag 1/3 & 3/3
>>
>> Reviewed the changes and mostly looks good with some minor nits added to
>> the individual patches.
>>
>> Small request -
>> Could you please also update test results with v3 in your changelog
>> (since you mentioned we are able to reproduce the issue easily with your
>> test code).
>
> I tested this fix with the program I shared in cover letter. The watchdog
> was successfully stopped even when H_WATCHDOG is called form crash
> handler.  I will share my test details in v3 cover letter also.
>
>>
>>
>> aah one other thing I just noticed since you are ccing stable and you
>> added a Fixes tag in patch-3.
>> Patch-3 alone cannot be easily backported now due to patch-1 and
>> patch-2. There must be a way to define the dependencies if you are
>> looking for backporting the fix patch to stable tree, please check that
>> and follow that accordingly in v3.
>
> I thought about that as well, but since they are part of the same patch 
> series,
> I assumed they would be picked together. However, I don't think that 
> will work
> in all cases.
>
> I checked the older commits and noticed that a backport note was added. 
> I think
> we can do the same for the fix patch. I'll add a note indicating that the
> following patches should be backported first:
>
> powerpc/pseries: Move H_WATCHDOG definitions to a common header
> powerpc/pseries: Handle and log pseries-wdt registration failures
>
> Since these patches are not upstream yet, I'll refer to them by their 
> commit titles.
>
> Does that look good to you?
>

Documentation/process/stable-kernel-rules.rst
  Note that for a patch series, you do not have to list as prerequisites the
  patches present in the series itself. For example, if you have the following
  patch series::

    patch1
    patch2

  where patch2 depends on patch1, you do not have to list patch1 as
  prerequisite of patch2 if you have already marked patch1 for stable
  inclusion.


In that case, I think, we should mark all 3 patches for stable inclusion.

  patch 1/3   Cc: stable@vger.kernel.org
  patch 2/3   Cc: stable@vger.kernel.org
  patch 3/3   Cc: stable@vger.kernel.org
              Fixes: 69472ffa6575 ("watchdog/pseries-wdt: initial support for H_WATCHDOG-based watchdog timers")

-ritesh